2. Pertaining to something which takes place every day: A good diurnal habit is to brush the teeth in the morning and in the evening on a regular basis.
Diurnal newspapers are delivered to George's mailbox from Monday to Saturday.
3. Descriptive of a book for daily use: On their trip in Africa, Lynn kept a diurnal record in her diary about the sights she and her husband saw and their experiences along the way.
4. Characteristic of a living creature which is active during the day and inactive during the night: Apes are considered to be diurnal animals, since they are busy and lively only from morning until late in the evening.
5. A reference to a flower which opens throughout the daylight and closes at night. There are specific diurnal plants like the morning glory and the crocus.
Go to this Word A Day Revisited Index
so you can see more of Mickey Bach's cartoons.
Humans are primarily diurnal creatures
If people were really at home under the light of the moon and stars, they would go into the darkness happily and the midnight world would be visible just as it is to the vast numbers of nocturnal species on the Earth.
Instead, people are generally diurnal creatures, with eyes adapted to living in the sun's light. This is considered to be a basic evolutionary fact, even though most people don't think of themselves as diurnal beings any more than they think of themselves as primates, or mammals, or Earthlings.
Yet, it's the only way to explain the light pollution that humans have done to the night. Ill-designed lighting has washed out the darkness of night and radically altered the light levels, and light rhythms, to which many forms of life, including mankind, have adapted.
Wherever human light spills into the natural world, some aspect of the lives of other creatures is affected; including migration, reproduction, and feeding.
In most cities, the sky looks as though it has been emptied of stars, leaving behind a vacant haze that mirrors the fear people have of the dark and resembles the urban glow of dystopian science fiction; which includes, societies or states in which the conditions of human life are characterized by misery, poverty, oppression, violence, disease, and pollution.